3008-40-0

Usage

Synthesis Reference(s)

Chemistry Letters, 15, p. 1939, 1986The Journal of Organic Chemistry, 51, p. 1419, 1986 DOI: 10.1021/jo00359a008Tetrahedron Letters, 28, p. 551, 1987 DOI: 10.1016/S0040-4039(00)95779-4

InChI:InChI=1/C8H12O2/c9-7-5-3-1-2-4-6-8(7)10/h1-6H2

Synthetic route

1,3-cylohexanedione (504-02-9) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With aluminum (III) chloride; Oxone In water at 20℃; for 1.5h;	97%

2-chlorocyclopentane-1-ol (69578-06-9) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With iron(III) chloride hexahydrate In water at 100℃; for 0.166667h;	80%

2-keto cyclopentanone acetal (109459-54-3) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With sulfuric acid; silica gel In dichloromethane for 24h; Ambient temperature;	73%
With sulfuric acid; silica gel In dichloromethane	60%

1-nitrocyclopentene oxide (109314-64-9) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With chloro-trimethyl-silane; triethylamine Mechanism; 1.) DMSO, dichloromethane, 0 deg C, 5 h; 2.) dichloromethane, 0 -> 30 deg C, 1 h; further α-nitroepoxides;	72%
With triethylamine; tetrakis(triphenylphosphine) palladium(0) In benzene for 7h; Heating;	50%
With chloro-trimethyl-silane; triethylamine 1.) DMSO, dichloromethane, 0 deg C, 5 h; 2.) dichloromethane, 0 -> 30 deg C, 1 h; Yield given. Multistep reaction;
With chloro-trimethyl-silane; triethylamine 1.) CH2Cl2, 0 deg C, 5 h, 2.) CH2Cl2, 0 deg C to r.t., 1 h; Yield given. Multistep reaction;

2-chlorocyclopentanone (694-28-0) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With iron(III) chloride In water at 100℃; for 0.333333h;	66.47%

4,5-dioxo-cyclopentane-1,3-dicarboxylic acid diethyl ester (10088-87-6) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With hydrogenchloride Heating;	61.7%
With sulfuric acid man giesst auf Eis;
With sulfuric acid
With sulfuric acid

2-(methylthio)cyclopentanone (52190-34-8) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With CuCl2-CuO In water; acetone at 35℃; for 0.5h;	60%
With copper(II) oxide; copper dichloride In water; acetone at 35℃; for 0.5h;	60%

Cyclopentene oxide (285-67-6) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With oxygen; copper(II) bis(trifluoromethanesulfonate); dimethyl sulfoxide; bismuth at 100℃; for 2h;	52%

1,2-bis((trimethylsilyl)oxy)cyclopent-1-ene (6838-66-0) → cyclopentane-1,2-dione (3008-40-0) + 3-bromo-2-hydroxycyclopent-2-en-1-one (3019-83-8)

Conditions	Yield
With bromine In tetrachloromethane	A 15% B 40%

2-acetoxy-5-bromo-cyclopentanone → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With hydrogenchloride

2,3-dioxo-cyclopentanecarboxylic acid ethyl ester (872280-63-2) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With sulfuric acid

cyclopentanone (120-92-3) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With perchloric acid; bromamine T In water Thermodynamic data; Kinetics; Mechanism; effect of ionic strengths (with p-toluenesulphonamide), solvent isotope ratio (H2O-D2O) and solvent composition (H2O-CH3OH) on reaction rate was measured in the temp.range of 30-45 degC. Energy of activation: 18.26 Kcal/mol; enthropy -15.63 e.u.;
With perchloric acid; tripropylammonium fluorochromate (VI) In water; acetic acid at 24.9℃; Rate constant; Thermodynamic data; ΔH(activ.), ΔS(activ.), ΔG(activ.); further temperatures (308-328 K);
With selenium(IV) oxide; ethanol

chloramine-B (127-52-6) + cyclopentanone (120-92-3) → cyclopentane-1,2-dione (3008-40-0) + benzenesulfonamide (98-10-2)

Conditions	Yield
With hydrogenchloride; perchloric acid; sodium perchlorate In ethanol at 30℃; Kinetics; Mechanism; Thermodynamic data; ΔH(excit.), ΔG(excit.), ΔS(excit.), effect of concentration of reactants;

6,12,13-Trioxa-dispiro[4.1.4.2]tridecan-1-one → cyclopentane-1,2-dione (3008-40-0) + cyclopentanone (120-92-3)

Conditions	Yield
With dimethylsulfide In methanol dry ice-acetone to room temperature; Yields of byproduct given;
With dimethylsulfide In methanol dry ice-acetone to room temperature; Yield given;

selenium(IV) oxide (7446-08-4) + ethanol (64-17-5) + cyclopentanone (120-92-3) → cyclopentane-1,2-dione (3008-40-0)

(+-)-2-chloro-cyclopentanone-(1) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With water; iron(III) chloride

4,5-dioxo-cyclopentane-dicarboxylic acid-(1.3)-diethyl ester → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With carbon dioxide; sulfuric acid

2-chlorocyclopentanone (694-28-0) + aqueous FeCl3-solution → cyclopentane-1,2-dione (3008-40-0)

trans-2,5-dibromo-cyclopentanone → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
With water; silver(l) oxide

sulfuric acid (7664-93-9) + 4,5-dioxo-cyclopentane-1,3-dicarboxylic acid diethyl ester (10088-87-6) → cyclopentane-1,2-dione (3008-40-0)

sulfuric acid (7664-93-9) + 4,5-dioxo-cyclopentane-1,3-dicarboxylic acid diethyl ester (10088-87-6) → cyclopentane-1,2-dione (3008-40-0) + 2,3-dioxo-cyclopentanecarboxylic acid ethyl ester (872280-63-2)

Conditions	Yield
at 100℃; Product distribution;

sulfuric acid (7664-93-9) + 2,3-dioxo-cyclopentanecarboxylic acid ethyl ester (872280-63-2) → cyclopentane-1,2-dione (3008-40-0)

cyclopentadiene-(3.5)-diol-(4.5)-dicarboxylic acid-(1.3)-diethyl ester → cyclopentane-1,2-dione (3008-40-0) + 2,3-dioxo-cyclopentanecarboxylic acid ethyl ester (872280-63-2)

Conditions	Yield
With sulfuric acid at 100℃;

2-hydroxy cyclopentanone acetal (109459-50-9) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
Multi-step reaction with 2 steps 1: 38 percent / CrO3, pyridine / CH2Cl2 / 0.33 h / Ambient temperature 2: 60 percent / H2SO4, silica / CH2Cl2 View Scheme
Multi-step reaction with 2 steps 1: 75 percent / pyridine, Cr2O3, kieselguhr / CH2Cl2 / 0.33 h / Ambient temperature 2: 73 percent / silica gel, 15percent H2SO4 / CH2Cl2 / 24 h / Ambient temperature View Scheme

cyclopentanone (120-92-3) + diluted alcoholic KOH → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1.) NaNH2, Et(OCH2CH2)2OH / 1.) THF, 2 h, 2.) THF 2: 60 percent / CuCl2, CuO / acetone; H2O / 0.5 h / 35 °C View Scheme

1-nitrocyclopentene (22987-82-2) → cyclopentane-1,2-dione (3008-40-0)

Conditions	Yield
Multi-step reaction with 2 steps 1: 81 percent / 15percent H2O2, 2N NaOH / methanol / 0.08 h 2: 1.) ClSiMe3, 2.) Et3N / 1.) CH2Cl2, 0 deg C, 5 h, 2.) CH2Cl2, 0 deg C to r.t., 1 h View Scheme

cyclopentane-1,2-dione (3008-40-0) + 2-methyl-propan-1-ol (78-83-1) → 3-isobutoxy-2-cyclopentenone (5682-74-6)

Conditions	Yield
With toluene-4-sulfonic acid at 85℃; for 18h;	95%

cyclopentane-1,2-dione (3008-40-0) → 3-chloro-2-hydroxycyclopent-2-enone (105872-18-2)

Conditions	Yield
With N-chloro-succinimide In water; acetonitrile at 20℃; for 40h; Inert atmosphere;	94%

cyclopentane-1,2-dione (3008-40-0) → 1-hydroxycyclobutane-1-carboxylic acid (41248-13-9)

Conditions	Yield
Stage #1: cyclopentane-1,2-dione With N-benzyl-trimethylammonium hydroxide at 25℃; for 7h; Neat (no solvent); Stage #2: With hydrogenchloride In water pH=2.6;	89%

cyclopentane-1,2-dione (3008-40-0) → 3-bromo-2-hydroxycyclopent-2-en-1-one (3019-83-8)

Conditions	Yield
With N-Bromosuccinimide In water; acetone at 20℃; for 16h;	89%
With N-Bromosuccinimide In water; acetone at 20℃;

cyclopentane-1,2-dione (3008-40-0) + 1-styrenyloxytrimethylsilane (13735-81-4) → 3-(2-oxo-2-phenylethyl)cyclopentane-1,2-dione

Conditions	Yield
With ammonium cerium(IV) nitrate In acetonitrile at -35℃; Alkylation;	87%

cyclopentane-1,2-dione (3008-40-0) + 8-oxa-tricyclo[4.3.0.01,4]non-2-ene-5-methanol → 2-[(1R,4S,5R,6S)-1-(8-Oxa-tricyclo[4.3.0.01,4]non-2-en-5-yl)methoxy]-cyclopent-2-enone

Conditions	Yield
With 3 A molecular sieve; Amberlyst-15 ion exchange resin In dichloromethane at 45℃;	87%

cyclopentane-1,2-dione (3008-40-0) + p-toluenesulfonyl chloride (98-59-9) → 2-p-toluenesulfonyloxy-2-cyclopentenone (77183-95-0)

Conditions	Yield
With pyridine for 2h; Ambient temperature;	85.6%

cyclopentane-1,2-dione (3008-40-0) + (2S)-2-(methoxymethyl)-1-pyrrolidine (63126-47-6) → 2-((S)-2-Methoxymethyl-pyrrolidin-1-yl)-cyclopent-2-enone (96304-33-5)

Conditions	Yield
3 A molecular sieve In benzene for 10h; Ambient temperature;	85%

cyclopentane-1,2-dione (3008-40-0) + isopropyldimethylsilyl chloride (3634-56-8) → 2,3-bis-(i-propyldimethyl-siloxy)-cyclopenta-1,3-diene

Conditions	Yield
With 1,8-diazabicyclo[5.4.0]undec-7-ene; lithium bromide In tetrahydrofuran at -15 - 45℃;	83%
With 1,8-diazabicyclo[5.4.0]undec-7-ene; lithium bromide In tetrahydrofuran at -15 - 45℃; for 20h;	83.3%

cyclopentane-1,2-dione (3008-40-0) + 1-(3-Amino-5-nitro-naphthalen-2-yl)-tridecan-1-one (110551-09-2) → 2-(8-Nitro-3-tridecanoyl-naphthalen-2-ylamino)-cyclopent-2-enone (110551-10-5)

Conditions	Yield
In acetic acid	78%

cyclopentane-1,2-dione (3008-40-0) + (2,2-diethoxyvinylidene)triphenylphosphorane (21882-77-9, 53472-13-2) → 2-Ethoxy-2-cyclopenten-1-on (40006-64-2) + ethyl (triphenylphosphoranylidene)acetate (1099-45-2)

Conditions	Yield
In diethyl ether Ambient temperature;	A 75% B n/a

cyclopentane-1,2-dione (3008-40-0) + allyl alcohol (107-18-6) → 2-(allyloxy)cyclopent-2-en-1-one (108461-95-6)

Conditions	Yield
With toluene-4-sulfonic acid for 0.166667h; Dean-Stark; Reflux; regioselective reaction;	74%

cyclopentane-1,2-dione (3008-40-0) + 2,4-dimethylcarbonohydrazide (13782-38-2) → 2,4,9,11-Tetramethyl-1,2,4,5,8,9,11,12-octaazadispiro<5.0.5.3>pentadecan-3,10-dion (87785-60-2)

Conditions	Yield
In acetic acid for 1h;	69%

cyclopentane-1,2-dione (3008-40-0) + thiophosgene (463-71-8) → C6H5ClO2S (112621-65-5)

Conditions	Yield
With pyridine In dichloromethane for 0.5h; Ambient temperature;	65%

cyclopentane-1,2-dione (3008-40-0) + benzylamine (100-46-9) → 2-(Benzylamino)-2-cyclopenten-1-on (103025-54-3)

Conditions	Yield
With toluene-4-sulfonic acid In chloroform Heating;	65%

cyclopentane-1,2-dione (3008-40-0) + vinyl magnesium bromide (1826-67-1) → 2‐hydroxy‐2‐vinylcyclopentan‐1‐one (27332-51-0)

Conditions	Yield
In tetrahydrofuran at 20℃; Cooling with ice;	64%
In tetrahydrofuran	53%
In tetrahydrofuran

cyclopentane-1,2-dione (3008-40-0) + p-toluidine (106-49-0) → 2-(4-Methylphenylamino)-2-cyclopenten-1-on (112152-02-0)

Conditions	Yield
	63%

cyclopentane-1,2-dione (3008-40-0) + m-Anisidine (536-90-3) → 2-((3-methoxyphenyl)amino)cyclopent-2-enone (112152-08-6)

Conditions	Yield
	57%

cyclopentane-1,2-dione (3008-40-0) + acryloyl chloride (814-68-6) + (4-{[tert-butyl(dimethyl)silyl]oxy}butyl)amine (245660-15-5) → N-[(4-tertbutyldimethylsilyloxy)butyl]-N-(5-oxocyclopentenyl)acrylamide (1005736-34-4)

Conditions	Yield
Stage #1: cyclopentane-1,2-dione; (4-{[tert-butyl(dimethyl)silyl]oxy}butyl)amine In benzene for 2h; Heating; Stage #2: acryloyl chloride With N,N-diethylaniline In benzene at 20℃; for 1h; Further stages.;	56%
Stage #1: cyclopentane-1,2-dione; (4-{[tert-butyl(dimethyl)silyl]oxy}butyl)amine In benzene Reflux; Stage #2: acryloyl chloride With N,N-diethylaniline In benzene at 0℃;	56%

cyclopentane-1,2-dione (3008-40-0) + trimethylsilylacetylene (1066-54-2) → C10H16O2Si

Conditions	Yield
Stage #1: trimethylsilylacetylene With ethylmagnesium bromide In tetrahydrofuran at -5℃; for 0.5h; Inert atmosphere; Stage #2: cyclopentane-1,2-dione In tetrahydrofuran at -5℃; for 2h; Inert atmosphere;	55%

cyclopentane-1,2-dione (3008-40-0) + 4-aminoacridine-3-carbaldehyde (471913-33-4) → benzo[b]-1,10-phenanthroline (225-87-6)

Conditions	Yield
With potassium hydroxide In ethanol for 20h; Friedlaender reaction; Heating;	52%

cyclopentane-1,2-dione (3008-40-0) → 1,2,3,5,6,7-hexahydrodicyclopenta[b,e]pyrazine (31579-41-6)

Conditions	Yield
With ammonium formate In N,N-dimethyl-formamide at 85℃; for 2h; Schlenk technique; Inert atmosphere;	51%

Upstream product

• 120-92-3 cyclopentanone 
• 6838-66-0 1,2-bis((trimethylsilyl)oxy)cyclopent-1-ene 
• 109459-54-3 2-keto cyclopentanone acetal 
• 127-52-6 chloramine-B 
• 7446-08-4 selenium(IV) oxide 
• 64-17-5 ethanol 
• 694-28-0 2-chlorocyclopentanone 
• 7664-93-9 sulfuric acid 
• 10088-87-6 4,5-dioxo-cyclopentane-1,3-dicarboxylic acid diethyl ester 
• 872280-63-2 2,3-dioxo-cyclopentanecarboxylic acid ethyl ester 
• 504-02-9 1,3-cylohexanedione 
• 69578-06-9 2-chlorocyclopentane-1-ol 
• 22987-82-2 1-nitrocyclopentene 
• 109459-50-9 2-hydroxy cyclopentanone acetal 

Downstream Products

• 5682-73-5 2-isobutoxycyclopent-2-enone 
• 6782-74-7 cyclopentane-1,2-dione-bis-phenylhydrazone 
• 6635-29-6 cyclopentane-1,2-dione dioxime 
• 83846-49-5 3-chloro-cyclopentane-1,2-dione 
• 5057-99-8 trans-cyclopentane-1,2-diol 
• 66049-41-0 2-benzoyloxy-cyclopent-2-enone 
• 109733-52-0 cyclopentane-1,2-dione-bis-benzoylhydrazone 
• 110357-96-5 cyclohexane-1,2-dione-bis-acetylhydrazone 
• 100518-21-6 2-methoxy-cyclopent-2-enone-(2,4-dinitro-phenylhydrazone) 
• 94333-16-1 (3E,4E)-3,4-dibenzylidenecyclopentane 
• 112152-08-6 2-(3-Methoxyphenylamino)-2-cyclopenten-1-on 
• 112152-02-0 2-(4-Methylphenylamino)-2-cyclopenten-1-on 
• 77183-95-0 2-p-toluenesulfonyloxy-2-cyclopentenone 
• 110-15-6 succinic acid 

Relevant academic research and scientific papers

Regioselective reductions of 23-epoxy acetals with lithium aluminum hydride: A reinvestigation

Treatment of 2,3-epoxy acetals with lithium aluminum hydride gave the corresponding 2-hydroxy acetals, instead of the previously reported 3-hydroxy acetals.

Kinetics and mechanism of bromamine-T oxidation of some cyclic ketones in acidic media

Kinetics of the oxidation cyclopentanone and cyclohexanone by bromamine-T(BAT) have been reported in perchloric acid media. A zero order dependence to BAT and first order dependence on both ketones and hydrogen ion concentrations have been observed. Observed stoichiometry, zero effects of ionic strength of the medium and p-toluenesulphonamide (TSA) and a negative dielectric effect point to a mechanism involving acid catalysed enolisation of ketones in the slow and rate determining step, followed by its subsequent fast interaction with BAT giving corresponding 1,2-diketones as final products. A solvent isotope effect (kD2O/kH2O = 2.0-2.2 (35°), 2.1-2.3 (40°) and 2.2-2.4 (35°), 2.3-2.5 (40°) for cyclopentanone and cyclohexanone, respectively) has been observed. Various thermodynamic parameters have been computed.

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The kinetics of oxidation of cyclohexanone, cyclopentanone, cycloheptanone, cyclooctanone and various alpha substituted cyclohexanones by pyridinium fluorochromate(PFC) has been followed under pseudo-first order conditions in aqueous acetic acid medium in the presence of HClO4. The reaction is first order both in oxidant and substrate. The rate increases linearly with increasing [HClO4]. The salt and solvent influences together indicate the reaction to be an ion-dipole type. The stoichiometry between the substrate and oxidant is 1:2 and the product of oxidation is 1,2-diketone. The relative reactivities of various cyclic ketones have been rationalised on the basis of conformational differences and steric factors.